It may be worth noting that developers don't necessarily need official apps for everything. That is, github becomes an implicit app store because we can build locally and push to our own devices.
I suspect this to be the only means by which Emacs will become available on iPhoneOS, for instance. Considering the intended user base, that's acceptable as a starting place.
(To preempt certain class of questions: Use the "happy hacker"/"das keyboard" concept by implementing an unmarked keyboard underneath a partially transparent background, so you maximize text on screen while also accommodating typing without external keyboard. For Emacs in particular, just hit C-l or otherwise scroll when cursor lands beneath fingers. That's one step closer to YCRFS5...)
I suspect this to be the only means by which Emacs will become available on iPhoneOS, for instance. Considering the intended user base, that's acceptable as a starting place.
(To preempt certain class of questions: Use the "happy hacker"/"das keyboard" concept by implementing an unmarked keyboard underneath a partially transparent background, so you maximize text on screen while also accommodating typing without external keyboard. For Emacs in particular, just hit C-l or otherwise scroll when cursor lands beneath fingers. That's one step closer to YCRFS5...)